Assignment: Temperature Sensitive Paints

Temperature Sensitive Paints

Temperature sensitive paints (TSP) allow non-invasive time resolved temperature and heat transfer distribution measurements at the interface between a wall and fluid. The paints are excited using UV light. A change in fluorescence intensity is used to infer the temperature. Advantages over infrared thermometry include the ability to measure substrates that are opaque to IR (e.g. plexiglass, plastic films), use of low-cost optical cameras and optics, no self-emission from substrates or windows to complicate data interpretation, high speed, and high spatial resolution.

We performed quenching (rapid cool-down) experiments of an aluminum container (vial) in liquid nitrogen. In one case, we attached a tape to the vial. As shown in the figure below, the vial with the tape cools much quicker than without a tape. Although we have a qualitative explanation for this process, we like to understand the underlying phenomea by measuring the temperature of the surface of the tape non-invasively. Temperature sensitive paints are seen as a potential solution for these measurements.

In this assignment the following activities are foreseen:

1) Calibration of the TSP. TSP materials are procured and temperature controlled plates are available in our lab.

2) Apply the TSP on a specimen and measure the temperature distribution during quenching.